Field of the Disclosure
The present disclosure relates to a coding and modulation apparatus and method. Further, the present disclosure relates to a transmission apparatus and method. Still further, the present disclosure relates to a computer program and a non-transitory computer-readable recording medium.
Description of Related Art
Modern communications systems typically employ, among other elements, a coding and modulation apparatus (as part of a transmission apparatus) and a decoding and demodulation apparatus (as part of a receiving apparatus). The coding and modulation apparatus is often part of a so called BICM (Bit Interleaved Coded Modulation) apparatus, which generally comprises (at the transmitter side) a serial concatenation of a FEC (Forward Error Correction) encoder, a bit interleaver, and a modulator, which uses spectral efficient modulation such as multilevel PAM (Pulse Amplitude Modulation), PSK (Phase Shift Keying), or QAM (Quadrature Amplitude Modulation). It should be noted that hereinafter, whenever QAM is mentioned it should be understood as a generally term covering PAM, PSK and QAM.
BICM allows for good performance over both non-fading and fading channels due to the use of the interleaver and/or the FEC encoder. It has a reasonable decoding complexity as opposed to multilevel coding (MLC) coding schemes and is thus used frequently in communications systems, such as in all DVB systems, powerline communications (e.g., Homeplug AV, DAB, LTE, WiFi, etc.).
Generally, the coding and modulation capacity, such as the BICM capacity in systems using a BICM apparatus, is considered as a target function, and it is desired to find optimum constellation points such that this capacity is maximized, often subject to a power normalization, i.e., the average power of the constellation points should be normalized to e.g. 1.
The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventor(s), to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present disclosure.